Train dispatching system for railroads



2 Sheets-Sheet l O. H. DICKE TRAIN DISPATCHING SYSTEM-FOR RAILROADS Original Filed April 2, 1927' March 9, -1937.

March 9, 1937. o. H. DlcKE TRAIN DISPATCHING SYSTEM FOR RAILROADS original Filed April 2 1927 2 Sheets-Sheet 2 ivd@ EN. Qu

Patented Mar. 9, 1937 TRAIN DISPATCHING SYSTEM FOR RAILROADS Oscar H. Dicke, Rochester, N. Y., assignor to General Railway Signal Company,rRochester,

Original application April 2, 1927,l Serial No.

180,475. Divided and this application 3, 1929, Serial No. 383,227

10 Claims.

This invention relates to a train dispatching system in which the movement of trains is dispatched by wayside signal indications (or cab signal indications where cab signals are used) and more particularly to the control and indication mechanism, affording a large number of controls for governing or dispatching the train movements and affording a large number of indications for indicating the movement of the trains, employing a small number of line Wires and circuits.

This application is a division of my prior application Ser. No. 180,475 led April 2, 1927. It

has heretofore been proposed in an application for` l5 patent led by S. N. Wight Serial No. 120,423 iiled July 3, 1926, to `dispatch the movement of trains through the medium of manual control superimposed upon starting and entering signals at passing sidings of a single, or double track .30 railway system, which starting and entering signals are controlled by track circuits and the like in accordance with traffic conditions ahead. This superimposed manual control permits such signals to clear only in accordance With traiic 25 conditions, and affords means whereby any one or more of such signals may be held at stop. In said Wight application provision has also been made for safely operating a switch machine at a distant point in response to manual control 30 means controllable by the dispatcher at a local tower. In the particular arrangement of the apparatus disclosed vin said Wight application the direction in which traffic may move through the single track joining two passing sidings is 35 determined by the sequence in which signals governing the entrance of trains into such single track section are cleared. That is, assuming that all the signals governing the entrance and departure of trains into or out of either end of a 40 single track section are held at stop, and it is desired to set up east bound traliic, this may be accomplished in the Wight application by permitting clearing of the signals at the West end of the single track section iirst and then per- 45 mitting clearing of certain signals at the east end of such single track section, in which event 'the starting signals at the west end of such single track section will clear, but the starting signals at the east end of such single track section will 50 be held at stop. Obviously, this idea of controlling the direction in which traflic may move in a single track section by the sequence in which signals are cleared was resorted to by Wight in order to obtain additional controls without the 55 need of additional line circuits, bearing in mind August s that the distance between the dispatchers tower I and the passing siding in some cases is many miles. In the applicationvof Wight there has also been disclosed means for-giving indications as to changes of the occupancy of track circuits, as distinguished from means for continuously indicating the condition of occupancy of a track circuit.

In accordance with the present invention it is proposed to control the clearing of signals for the purpose of dispatching the movement of trains in a signal system as shown in the Wight application, to operate the switch machines, to receive continuing indications as to the position of each of the various switch machines, and to indicate continuously the condition of occu- Dancy of Various track circuits of asection of the railroad including-a large number 'of passing sidings, all through the medium of a very few control circuits, some-of which include the same or common return wire. Before mentioning the specic objects, purposes and characteristic features of the invention it isdeemed expedient to iirst consider the problems encountered in endeavoring to reduce the control circuits for a system such as above mentioned. In the rst'instance it should be understood that it is diilicult to control by a single means .an exceedingly large `number of signals independently of each other, remembering that certain trains may be desired to be held at stop While it is desired to allow many other trains to proceed. In the second instance, ii it is desired` to give indications as to the condition of occupancy of all of the track circuits ci the railway system there is a possibility of not only a large numberj of track circuits being occupied at the same time but there is also a possibility of track circuits being entered upon at the same instant, so that it is very diiiicult to obtain simultaneous control as to the occupancy of these track circuits.

In view of the foregoing and other important considerations it is proposed in accordance with one form of the invention to providea single line circuit which connects to a large number of'synclironously rotated contacts, which'contacts Wipe over or otherwise closecircuits to successive segments, these segments being connected to control suitable responsive means in such a way that if one of these segments at one location is energized a responsive. means connected to corresponding segment at a distant point is energized as a result of the energy applied to the first mentioned segment. In other words, it is proposed to allot the use of the line circuit as ,tov time to each of a circuit being repeated once during each revolution of the. synchronized contacts.

More specifically, it is not only proposed to energize a relay at a distant point through the momentary connection of this relay to a control lever as a result of the allotment of the line circuit as just mentioned, but it is further proposed to complete a stick circuit for such relay throughout the entire remaining period or cycle of operation of the synchronous contact.. In other words, if the line circuit is allotted to a particular function for the first 50th part of a revolution of the synchronized contacts, a relay can be picked up at a distant point during this first 50th of a revolution, and with the relay once picked up a stick circuit is completed which will maintain the relay energized through the remaining 49/50th of the control cycle. In the particular embodiment oi the invention disclosed in this application it is proposed to receive indications at the dispatchers tower as to the condition of occupancy of track circuits and the positions the various switch machines are assuming at a particular time by theI synchronized control arrangement above mentioned, and to control the various signals and switch machines located along the railway track by the train dispatcher from the tower through the medium of suitable code responsive selective devices. In this connection it should be borne in mind that the dispatcher is in a position to operate the various switch machines and clear the various signals or put them to stop one at a time at such time as he desires, so that there is no conflict due to simultaneous transmission of selected distinctive codes.

Other objects, purposes and characteristic features of the invention will appear as the description thereof progresses, and will in part be obvious from the drawings when taken in connection with the application of Wight above mentioned.

In describing the invention in detail reference will be made to the accompanying drawings in which:-

- Figs. 1A and 1B show a train dispatching system in which the manual supervisory control that the dispatcher has over the various signals and switch machines is carried out through the medium of selective relays which may be selectively operated by distinctive selective code impulses, and wherein indications as to the operated position of the various switch machines and the condition of the various track circuits is indicated by a synchronized control arrangement such as shown in Figs, lA and 1B; and

Fig. 2 is a side view of the essential elements of a selective relay responsive to a particular codeonly and specifically illustrates contacts capable of opening a circuit if a particular code of impulses is impressed thereon,

Fig.v 3 shows a device such as ilustrated in Fig. 2 except that it illustrates the parts capable of closing instead of opening a circuit; and

Fig. 4 shows a front view of the apparatus shown in Fig. 2.

Apparatus Figs. 1A and 1B.Referring to Figs. 1A and 1B, and bearing in mind that the system shown therein is one wherein the outlying signals and switch machines are controlled from the dispatchers tower DT, through the medium of code responsive means, and wherein indications are transmitted as to the operated positions of the various switch machines and the condition of occupancy of various track circuits to the tower,

plurality of functions, this allotment of the line all through the medium of one line wire one common return wire and associated mechanism whereby the use of the line wire is allotted as to time to a large number of functions. Referring to Fig. 1B in which there has been shown a single track section O, of a single track railway system, the passing siding N and a portion of the passing siding P. Although, the dispatching system embodying the present invention may be applied to double track railways signalled with any type of wayside signalling means, for convenience it is assumed that the signalling system shown is one of the absolute-permissive-block type such as shown in detail in the application of Wight mentioned. In the particular arrangement shown, the signals governing west bound traflic have been assigned reference numbers I, 3, 5 and 1, as shown, the signals governing east bound traiiic containing reference numbers 2, 4, 6 and 8, respectively, and the siding signals have been designated D with a preiix corresponding to that of the corresponding main signal.

Although the wayside signals illustrated are signals of the semaphore type, and although the starting and entering signals have vbeen illustrated as two position signals, all of these signals are preferably three aspect signals, and may be either of the semaphore, the color light, position light or position color light signals, semaphore signals having been illustrated for convenience. In this connection it should be noted that the signals shown adjacent the track switch IS and 8S, namely signals I, ID, 2, 2D, l, 1D, 8 and 8D all have square blades, whereas the remaining signals have pointed blades, this distinctive configuration of the various blades is to conventionally illustrate that the signals I, ID, 2, 2D etc. are stop and stay signals which must not be passed unless one of the governing signals indicates proceed, and the intermediate signals 3, 4, 5 and 6 having pointed blades conventionally designate permissive signals which may be passed at low speed even though they indicate stop. The switches at the west end of passing sidings N and P have been designated 8S and the track switch at the east end of passing siding N has been designated IS. These switches are preferably operated by suitable power operated switch machines, and these switch machines have been designated SMW and SME, respectively. Adjacent the switches 8S and IS are contained fouling or detector track circuits of the usual construction, which are used to indicate the presence of a train on those parts of the main track and siding which conllict with each other, and these detector track circuits include track relays TW and TE, respectively. In addition to the starting signals 2 and 'I there are provided dwarf signals 2D and ID which govern the movement of traic oi of the siding into the main track, and in addition to the entering signals I and 8 .shown there are provided take siding signals or lower arm signals ID and 8D for governing the movement of trains into the siding. Each of the various signals is controlled by a home relay designated I-I with a preiix corresponding to the reference number of the signal, that is the signals 2 and 2D are governed by the home relay 2H, and the position the switch machine SME is assuming, the signals I and ID are governed by the home relay IH and the position the switch machine SME is assuming at the time; the signals 8 and 8D are controlled by the home relay 8H and in accordance with the position the switch machine SMW is assuming at the time, and the l with the arrangement shown in the application of Wight heretofore referred to, and the signals 8, 8D, I and 'ID and the switch machine SMW are controlled in accordance with the position of the control relay ZW and also depending upon l whether the signal 2 at the west end (not shown) of the single track section M is clear at the time all in a manner as explained in said Wight application. In this connection it is desired to point out that the control circuits for the signals I, ID,

2, 2D, 'I, TD, 8 and 8D are not exactly the same as those shown in the Wight application mentioned, partly because the control for the caution indication has been omitted and partly because a slightly different interlock between signals is employed,

35 and it is to be understood that the control circuits as shown in the Wight application may be used, if desired.

The system shown also includes an approach locking relay AL which may be controlled in the same way as is the relay CR shown in the Wight application. This approach locking relay prevents the switch machine being operated in the face of an approaching train.

Referring more particularly to Fig. 1A of the drawings in which a portion of the apparatus in the dispatchers tower DT has been illustrated, the dispatchers tower DT shows a miniature track layout including the passing siding N, a single track section O and a portion of the passing P. At the east end of the passing siding N has been shown an indicator comprising an indicating lamp TEL, which is controlled to continuously indicate the condition of occupancy of the detector track circuit including track relay TE through suitable means more particularly described hereinafter. A similar indicating lamp TWL being provided at the west end of the passing siding N. Also, at the east end of the passing siding N of the miniature track layout are provided two lights preferably distinctive in color of which the light EN indicates, or is illuminated, when the track switch IS at the east end of passing siding N is in its normal position and the light ER indicates when this track switch is in its reversed or take siding condition, similar switch indicating lamps WN and WR being provided at the west end of the passing siding N in the dispatchers miniature track layout. The detector track circuit indicating lights TEL and TWL are controlled by indicating stick relays TEI and TWI, and the switch machine indication lamps EN-ER and WN-WR are controlled by polar stick relays SMEI and SMWI, respectively, in a manner as more clearly described presently.

The apparatus in the dispatchers tower also includes audible signals to inform the dispatcher as to the change in the occupancy of a track circuit, that is to say, a change in the indicating condition of any one of the lamps TWL, TEL, etc. In the particular arrangement shown the direct current for energizing the lamps TWL, TEL etc. flows through a common wire including the primary winding of a transformer 5t, the secondary winding of which transformer is connected in series with the single polarized bell 5Ib having two gongs of dierent tones, one of which sounds a single stroke upon an increase of current in the primary of transformer and the other of which sounds similarly upon a decrease in this current. In other words, one bell sounds one tap, when current flows in one direction and the other bell responds when current flows in the other direction. Since the increase of current in the primary winding of transformer 50 causes current to flow in one direction in the secondary winding thereof and a decrease of current in the primary winding of transformer 50 causes current to flow in the other direction in the secondary thereof, one of th'e bells will sound when a lamp is lighted and the other bell will sound when an indicating lamp is extinguished. The bells are preferably distinctive in tone so that the dispatcher is distinctively audibly informed when a light is lighted and extinguished.

As heretofore mentioned the line wire IIIW is to be allotted with respect to time for serving a large number of different functions, and in order to have the line wire IUW complete the various independent circuits at different times it is proposed to provide contacts at the dispatchers tower and at various points along the railway for making such connections simultaneously. In order to accomplish this, it is proposed to rotate contacts carried by different shafts synchronously. Although these contacts may be rotated by synchronous motors having their field windings and rotor windings energized by alternating vcurrents of different frequencies, may be rotated by suitable step by step mechanism, or may be rotated by motors, the particular arrangement shown in in synchronism with the magnetic field, and the motor will then rotate at exact synchronous speed. The various synchronously driven shafts I are driven by the synchronous motors SM through slip clutches I5, Worms I6 and Worm wheels II as conventionally shown. The look magnets III of the system are connected directly in multiple, or across, the alternating current transmission line, so that the lock magnets are normally energized, but are de-energized upon power failure, and the like. If power should fail on the alternating current transmission line II2 from which the various synchronous motors SM and lock magnets III receive their energy the various lock magnets III will be de-energized and will allow the springs II9 to pull the stop pawls II3 containing rollers II4 toa position so that they engage the stop lugs II5 on the worm wheels I'I. The movement of the stop arms II3 by the springs II9 is limited by the stops II6. It is therefore seen, that upon power failure all of the various contact arms of the synchronous system will be brought to a stop at exactly the same point in their operating cycle. This provision is made so that upon re-energlza- ,tion of the transmission line II2, all of the m0- tors will start to rotate their respective contact arms at the same point, and if these motors all have the same starting characteristics the time required for them to reach their synchronous speed is the same, as is assumed and will be the case in practice, as a result of which all of the rotating contact arms will again rotate in synchronism even though there has been a power failure. Since all of the synchronous motors SM run at exactly the same speed the rotating Contact arms will of course remain in synchronism after once synchronized. In other Words, in the arrangement shown in the drawings the synchronous contact arms are rotated by motors which operate at exactly the same speed and provision has been made for bringing these contact arms in synchronism upon starting of the various synchronous motors.

Operation of Figs. 1A and 1B.-In order to get a more clear understanding of the apparatus conventionally illustrated in Figs. 1A and 1B it is deemed expedient to now consider the operation of the system. Before the movement of trains are considered in the operation of the system the position of the switch machinesl SME and SMW should iirst be ascertained as manifested by the indicating lights on the dispatchers miniature track layout. Figs. 1A and 1B should be laid end to end `to illustrate the system. Referring to Fig. 1B it will be noted that the switch machine SME is assuming the normal position, and that with it in this position the positive side of the battery 33 is connected to the stationary Contact 3| of thesynchronizing mechanism located at passing siding N. From this it will be seen that the moment the rotating arm 32 assumes a position to contact with the stationary Contact 3i that the rotating contact 33 located at the dispatchers tower DT is then in engagement with the stationary contact 34, so that, for an instant at least the positive side of the battery 3D is connected'to the stationary contact 3@ and in turn permits current to now through the following circuit:-beginning at the plus terminal of the battery 30, contact 35 of the switch machine SME, stationary contact 3| and movable contact 32 of the synchronizing mechanism lo- I cated at siding N, line wire IilW, movable contact 33 and stationary contact 3i.- of the synchronizing mechanism located in the dispatchers tower DT, through the winding of the indicating relay SMEI to the common return wire C connected to the midpoint of the battery 30. With this circuit momentarily completed the indicating relay SMEI is picked up closing its front contact and completing the following stick circuit:- beginning at the positive side of the battery 31 located in the dispatchers tower, polar contact 35 oi the indicating relay SMEI, front neutral stick contact 39 of this same relay, winding of this relay to the common return wire C, to the rotating arm 45 of the synchronizing mechanism located in the dispatchers tower DT to the stationary contact 4| cooperating with the movable contact 45, back to the neutral point of battery 31. It may be pointed out here, that stick relays TWI and TEI may be stuck up by similar stick circuits to the one just traced but including batteries 3l'2 and 313, respectively. With this stick circuit completed the indicating relay SMEI is energized through the remaining part of the revolution, or until the rotating contact 33 again reaches the stationary contact 34. In other words, energy is transmitted from the distant passing siding N to the indication relay SMEI over the contacts 3| and 3d and the line wire IDW through `a small fraction of one revolution of the synchronizing mechanisms, and this indicating relay is then stuck up for the rest of the revolution of the contacts 32 and 33, and so long as the contact 3| at the passing siding N is connected to the positive pole of the battery 30 the indicating relay SMEI in the tower DT will remain energized. With the indicating relay SMEI energized positively, that is, with its polar contact I3 to the right the normal indicating lamp EN is illuminated through the following circuit to indicate that the switch machine SME is in the normal position:-beginning at the terminal B of a suitable source of current, front contact I2 of the indicating relay SMEI, polar contact I3 in its right hand position, through the indication lamp EN back to the common return Wire C connected to the other side of said source.

In the same manner as just described the indicating relay SMWI is picked up and stuck up through similar circuits and contacts which have been assigned the same reference numbers with distinctive exponents 1 (one). From this it will be seen, that in the same manner as just explained the relays SMEI and SMWI may also be picked up and stuck up in their reverse position when the switch machines assume the reversed or take-siding position, in which event the lamps ER and WR, respectively, will be illuminated. It is to be understood that during operation of the switch machines, such as SME, the battery 30 is not connected to the contact 3| and therefore the relay SMEI is deenergized while the synchronous contacts 33 assume a position to engage contact 34 (the stick circuit for this relay then being open at the gap in stick contact 4|) so that, this relay SMEI will thereafter assume the de-energized position. In this connection, if desired, the stick circuits for the relays SMEI and SMWI may be omitted and the energization of the indicating lamps EN, ER, WN and WR may be controlled by the polar contacts I3 and |31 alone (with contacts l2 and l21 omitted), it being understood that the polar contacts of these relays remain in the position to which they were last actuated.

The control relays ZW and ZE located at the ends of the passing siding of the system, of which the passing siding N and a portion of the passing siding P only has been shown, control the switch machines and wayside signals in exactly the same way as described in the parent application. These control relays ZW and ZE are however controlled from the dispatchers tower DT by different apparatus and in a different way than are those of the parent application. In the arrangement shown the relays ZW and ZE may be energized in the normal direction, in the reversed direction or may be de-energized in response to distinctive co'de impulses over the telephone line |I1.

In order to describe the manner in which the control relays ZW and ZE are controlled from the dispatchers tower it is deemed expedient to rst briefly consider the operating characteristics of the code responsive selective relays SR conventionally shown in Figs. 2, 4 and 1B. Referring more particularly to Figs. 2 and 4 in which a code responsive selective relay SR has been conventionally shown which is of a construction such as shown in the patent to VGeer and Leake No. 1,118,120 dated Nov. 24, 1914, and reference, may be had to this patent as to the detailed construction of the code responsive selective relay used for controlling the various control relays ZE and ZW, and for ringing bells for the'purpse of calling operators, train men or local ticket agents to the telephone. The code responsive selective relay SR includes a polar armature which may be operated from its neutral to one or the other extreme position depending upon Whether positive or negative current is caused to ow through its winding ||8, so that if current ilows in one direction (positive current) the armature is operated differently than if current iiows in the other direction (negative current). The code responsive selective relay is so constructed that if it assumes its released or normal position the application of positive impulses through its winding will cause the arm 44 carrying a plunger 6| to be moved step by step one step for each impulse of positive current, through an arcuate path in a counterclockwise direction about the shaft 38. `If now negative impulses are applied to the winding ||8 of the selective relay SR the other arm 46 carrying a contact operator 62, which contains a piece of insulation 91, is caused to rotate in a clockwise direction about shaft 38. From this it readily appears that a specific number of positive impulses and a specific number of negative impulses will be necessary to bring both of these arms in a particular relation with stationary contacts arranged about a similar arc. If now the specific number of impulses applied to the winding ||8 of the relay SR are of` such a number as to bring the arm 44 in alignment with the contacts |26V (see Figs. 3, 4 and 1B), and then the necessary number of negative impulses are applied to this winding ||8 to move the arm 46 in alignment with the same contact |26, the functioning of the interengaging mechanism of the selecting relay SR will be modified, in that after these arms 44 and 46 have been moved from their normal position the re-application of positive current to the winding thereof will not operate the arm 44, step by step, as it did heretofore, but will cause the plunger 6| to be pushed outwardly. The plunger 6| will continue to remain in its outward position so long as the positive current is maintained. With the plunger 6| positioned outward (see Fig. 2) it will cause the contact operator 62 to be swung about its pivot 64 thereby causing the insulating portion 91 to engage' the stationary contact |26 and move it from engagement with the other stationary contact |26, and a circuit carried through contact |26 will be opened. Further, the selecting relay SR is of such construction that the arms 46 and 44 will be restored to their normal position when the positive impulse which operated the plunger 6| and followed the negative impulses is discontinued. In other words, positive impulses operate the arm 44 step by step, negative impulses operate the arm 46 step by step, and then the application of a positive impulse will operate the plunger 6| and the discontinuation of this positive impulse will cause the arms 4| and v44 to be returned to their normal position. In substantially the same way as just described with respect to actuation of contacts |26 the arms 46 and 44 may be brought in alignment with the contacts |25, providing the requisite numbers of positive and negative impulses are transmitted in the proper sequence, which requisite numbers of impulses will of course be different from those necessary to bring these arms in alignment with the contact |26 just described. If the arms 46 and 44 are brought in alignment with the stationary contact |25 as just described, the application of positive impulses to the winding of the selecting relay SR thereafter will cause the contact operator 62 to force the contact |25 in engagement with the other` stationary contact |25 andcom-` plete a circuit so long as the positive current application is continued.

In order to make it more convenient for the dispatcher to operate the various neutral relays in response to various distinctive codes, suitable calling keys or control keys are preferably provided, and such control keys |40, |4|, |42, |43,` |44 and |45, and ringing keys |46, |41, |48 and |49 have been conventionally shown in Fig. v1A of the drawings. For a detailed description of the construction of these controlling and ringing keys, reference may be had to the patent to Geer and Leake No. 1,105,766 dated August 4, 1914.

Operation Figs. 1A and 1B.-Let us assume that* the dispatcher located at the tower DT wishes to clear the signal 2 shown in Fig. 1B oi the drawings, which if he wishes to do, he must energize the control relay ZEfto its right hand position. In order to energize the control relay ZE to the right hand energized position the dispatcher will iirst be required to move the control lever LE (see Fig. 1A) located in the tower to the right hand dotted position so as to permit the use of the operating key |45. With the-circuit completed so far as the control relay ZE is concerned the operator will operate the calling or control key |45 which will cause six positive impulses, followed by four negative impulses followed by one positive impulse to be transmitted. Referring to Fig. 1B it will be noted that the contacts |25 will be closed in response toA a code consisting of six positive impulses and four negative impulses followed by one positive impulse. In other words, with the lever LE moved to the right hand position and the control key |45 operated at the dispatchers tower, the contacts |25 at the passing siding N are closed, thereby completing the following circuitz-beginning at the positive terminal of thebattery |50, wire |5|; contacts |2V5`of the selective relay SR, wires |52 and |59, winding of the control relay ZE, wire |53, back to the neutral point of the battery |50. With this circuit completed the control relay ZE will be energized to the right hand position and will thereby close the following stick circuit:- beginning at the positive side of the battery |50, wire |54, polar contact |55 of the control relay ZE, wire |56, neutral contact |51 of the control relay ZE, wire |58, contacts |26, wires |52 and |59, winding of the control relay ZE, wire |53, to the neutral point of the battery |50. With the control relay ZE energized to the right hand position through the stick circuit just traced the signal 2 will assume the proceed position, assuming of course that traffic conditions in advance thereof are clear, al1 as readily understood from the drawings. It is of course understood that the contacts |25 of the selective relay SR were only held closed for a short time, sufficient to allow the control relay ZE to pick up, and that the arms 46 and 44 of the SR relay have been returned to their normal position. In practice the dispatcher will leave the levers LE and LW shown in Fig. 1A of the drawings in the position in which f they were last used, and by so doing the position of these levers will inform him as to the energized or de-energized condition of the control relays ZE and ZW. Further it is to be understood that suitable indicators for indicating the sequence in which the levers for the ends of each single track section have been operated from their neutral position such as disclosed in said Wight application, may be used, if desired, whichif used will advise the'dispatcher what direction ofY traffic movement .has been set up in such single track section. .31. 1

Let us now assume that the'dispatcher located at' tower DT wishes to put the signal 2 to stop. In order to do so, he will move his lever LE to its neutral normal position, in which position this lever LE permits the use of the operating key |44. If now, the dispatcher operates the key |44 a code consisting of seven positive impulses followed by three negative impulses followed by one positive impulse will be transmitted, and the transmission of these impulses Will momentarily open the contacts |26 of the code responsive selecting relay SR located at the passing siding N. Itshould be noted that these contacts |26 are included in the stick circuit for the control relay ZE just traced, and that momentarily opening of this stick circuit will cause the control relay ZE to be deenergized, because momentary opening of this circuit will open the stick contact |51 after which reclosure of contacts |26 are not able to re-energize the control relay ZE.

Let us now assume that the dispatcher wishes to energize thecontrol relay ZE to its left-hand energized position, in order to operate the switch machine SME to the reverse position and in order to clear dwarf signal 2D.V In order to accomplish this he will be required to move his control lever LE to the left hand dotted position which position the control key |43 is in the circuit so that either positive or negative impulses may be transmitted from thebattery i60 located i n the dispatchers tower. If now, the dispatcher operates the control key |43, five positive impulses will be transmitted followed by five negative impulses, followed by one positive impulse. This distinctive code will cause closure of the contacts |24 of the selective relay SR, and the closure of these contactswill cause ,the control relay ZE to assume the left hand energized position by reason of closure of the following circuitsz--beginning at the negative terminal of the battery |50, Wire |62, contactl24, wires |63and |59, winding of the control relay ZE, wire |53, back to the neutral point of battery |50. With the control relay ZE assuming the left hand energized position in response to the closure of the circuit just traced, a stick circuit for this control relay ZE is completed, which circuit is exactly the same as the stick circuit heretofore traced exceptv that it includes the wire |64 instead of the wire |54. With the control relay energized to the reversed position the dwarf signal 2D may be caused to indicate clear through thev closure of the circuit for this signal readily traced in the drawings. It is of course understood that the control relay ZE may be deenergizedand the dwarf signal 2D be caused to indicate stop by the train dispatcher in the tower DT in response to movement of his lever LE to its middle neutral position and operation of control key |44, in a manner as already described.

In the same manner as just described with respect to the control relay ZE the control relay ZW may be picked up and stuck up into the right hand position in response to operation of the control key |42, which transmits three positive impulses followed by seven negative impulses followed by one positive impulse, which closes the contacts |22, the relay ZW may be then dropped by opening the stick circuit thereof which includes the contacts |23, and which contacts are opened if the dispatcher operates the control key |4|, the operation of which transmits four positive impulses followed by six negative impulses followed by one positive impulse; and the control relay ZW may be picked up to the left hand energized position and stuck up through the closure of contacts |2| of the code selective relay SR, which contacts are closed in response to operation of the control key |40, the operation of which transmits two positive impulses followed by eight negative impulses then followed by one positive impulse. It should be noted that the combination of impulses for each of the series of pairsof contacts has been designated by numbers having a prefix plus or minus as indicated in Fig. 1B of the drawings.

If ,the dispacther should desire to call one of the train crew to a telephone |10 located adjacent the switch machine SME the dispatcher will move the lever L in the tower to a position to connect the calling key |48, will then operate the calling key |48 and thereby transmit eight positive impulses followed by two negative impulses and then followed by one positive impulse, which distinctive code will close the contacts |21 of the code responsive selective relay SR, the closure of which contacts will ring the bell |1| by connectf ing it in a closed circuit with the battery |12. The dispatcher may then communicate over-the usual telephone apparatus including the telephone |13 at the dispatchers tower and the telephone instrument |10 at the `east end of siding N. No provision has been made for calling the "dispatcher to his telephone |13, because the dispatcher is supposed to be listening in on` the line all th-e time, either through the provision of a head set or the provision of a loud speaker in the oilice, so that anyone along the line who desires to communicate with the dispatcher need only call into his phone the word dispatcher or some other suitable term and the dispatcher will reply; Since all of the control and ringing keys are located in the dispatchers tower there is no possibility of two codes being transmitted at the same time unless the dispatcher wilfully operates two keys at the same time which he is 'not supposed to do. shown in Figs. 1A-1B only one line wire |0W has been illustrated, this line wire connecting the rotatable contact arm of each of the various synchronously controlled mechanisms located along the railway together, one arm being assumed to be used at each important point along the railway, additional line wires may be used which connect with additional synchronously driven contact arms, in the event that there are more functions to be handled than can conveniently be handled over one line wire through the length of time allotted to one rotation of the various synchronously driven shafts I4.

Having thus shown and described a specific embodiment of the present invention, it is desired to be understood that this has been done for the purpose of disclosing an application of the invention and in order to describe the invention rather thanfor the purpose of illustrating the exact apparatus preferably employed in practicing the same or illustrating the scope thereof; and it is further desired to be understood that various changes, modifications and additions may be made to adapt the invention to a particular railway system whether single track or double track and irrespective of the specific signaling system superimposed thereon, and that the synchronous and code responsive control systems may be used for operating switch machines irrespective of whether such switch Although in the arrangementy i machines are used on a railway system employing a train dispatching system of the wayside signal indicating type, and that other changes may be made as the particular exigencies of the case require, all without departing from the scope of the invention or the idea of means underlying the same except as demanded by the scope of the following claims.

What I claim ist- 1. In a train dispatching system of the wayside signal indicating type, the combination with a local oflice and a plurality of way stations, track switches and signals at each of said way stations, a detector track circuit associated with 7 each of said track switches, and a selector system of the multiple distinctive code type wherein each code is characterized by a plurality of distinctive impulses for controlling said switches and signals in response to manual supervision originating at said local cnice, and another selector system of the synchronous sequential indicating type for sequentially indicating the positions of said track switches and the occupancy of said detector track circuits, whereby codes may be taken advantage of where manual supervision is available and sequential non-interfering communication is rendered available where changes at a plurality of locations occur automatically.

2. In a train indicating system, the combination with a selector type system for positioning contacts in a central ofiice in accordance with traic conditions at various points along a railway system, a plurality of indicators controlled by said contacts and rendered effective by electrical energization thereof, and means included in a circuit portion common to all of said indicators for sounding an alarm for each change in the total number of indicators active at one time.

3. In a train indicating system, the combination with a selector type system for positioning contactsin a central oice in accordance with traffic conditions at various points along a railway system, a plurality of indicators controlled by said contacts and rendered effective by electrical energization thereof, and means for sounding one alarm for each increase and sounding a distinctive alarm for each decrease in the total number of indicators active at one time.

4. In combination, a railway system including a distant track switch, a switch machine for operating said track switch, a polar control relay having a polar contact which remains in the last energized position thereof even if said relay has in the meantime been deenergized, a selector system of the code type wherein each series of transmitted impulses denes a particular code one for controlling each of a plurality of such polar control relays including said polar relay over the same pair of line wires and each to a particular position by a distinctive series of code impulses, a normal operating circuit for said switch machine including said polar contact assuming one of its polar positions, a reverse circuit for said switch machine including said polar contact assuming the other of its polar. positions, a detector track circuit including a track relay associated with said track switch, a signal adjacent said track switch to govern the movement of traffic over said track switch, and means for preventing the control of said switch machine by said polar relay when said track relay is deenergized or said signal assumes a proceed position.

5. In combination, a railway system including a distant track` switch, a switch machine for operating said track switch, a polar control relay having a polar contact which remains in the last energized position thereof even if said relay has in the meantime been deenergized, a code type selector system for controlling a plurality of such polar control relays including said polar relay over the same pair of line wires and each in accordance with a distinctive codek of impulses transmitted by said system, a normal operating circuit for said switch machine including said polar contact assuming one of its polar positions, a reverse circuit for said switch machine including said polar contact assuming the other of its polar positions, and a front contact of an approach locking relay which assumes its deenergized position when there is a train approaching under proceed included in both said normal and said reverse operatingv circuit.

6. In combination, a railway system including a distant track switch, a switch machine for operating said track switch, a polar control relay having a polar contact which remains in the last energized position thereof even if said relay has in the meantime been deenergized, a selector system of the code type wherein each series of transmitted impulses denes a particular code for controlling a plurality of such polar control relays including said polar relay over the same pair of line wires and each to a particular position by a distinctive series of code impulses, a normal operating circuit for said switch machine including said polar contact assuming one of its polar positions, a reverse circuit for said switch machine including said polar contact assuming the other of its polar positions, and a front contact of an approach locking relay which assumes its deenergized position when a signal governing traiiic over said switch is at proceed included in both said normal and said reverse operating circuit.

7. In combination, a section of railway track including a track switch, a signal for governing trafc over said track switch, a switch machine for operating said track switch, a switch machine control relay, a signal controlling contact on said switch control relay controlled from a central ofce in accordance with the code character of a series of code impulses, a circuit for clearing said signal closed only if said track switch and said switch control relay assume corresponding positions and said signal controlling contact is closed, and means for preventing said switch machine being operated in response to a change in the position of said switch control relay when there is a train approaching said track switch under proceed traffic conditions.

8. In combination, a section of railway track including a track switch, a signal for governing traffic over said track switch, a switch machine for operating said track switch, a switch machine control relay controlled from a central oiiice in accordance with the code character of a series of code impulses, means for maintaining said switch machine control relay in its last actuated position, a signal controlling contact on said switch control relay controlled from a central office in accordance with the code character of a series of code impulses, a circuit for clearing said signal closed only if said track switch and said switch control relay assume corresponding positions and said signal controlling Contact is closed, and means for preventing said switch machine being operated in response to a change in the' position of said switch control relay when there is a train approaching said track switch under proceed traffic conditions, whereby said switch machine may be conditioned for a new position by operation of said switch machine control relay but operation of said switch machine is deferred until the approaching train has passed over said track switch.

9. In combination, an oice, a station, a section of railway track at said station including a track switch, a signal for governing trailic over said track switch, a switch machine for operating said track switch, a switch machine control relay, a signal controlling contact on said switch control relay, a line circuit connecting said ofice and said station, means at said office for transmitting over said line circuit any one of a plurality of series of electrical impulses each series comprising positive and negative impulses arranged in a pattern to dene a code, code responsive means for distinctively controlling said control relay and said contact depending o-n the character of the particular code received, and a circuit for clearing said signal closed only if said track switch and said switch control relay assume corresponding positions and said signal controlling contact is closed.

10. In combination, a section of railway track including a track switch, a signal for governing traic over said track switch, a switch machine for operating said track switch, a switch machine control relay, a distant control oflice, a. single circuit connecting said office and said section, a signal controlling contact on said switch control relay, means for transmitting from said oii'ice to said station over said line circuit any one of a plurality of series of electrical impulses each series comprising positive and negative impulses4 OSCAR H. DICKE. 

